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                                                                   EXHIBIT 10.20



                               CAERE CORPORATION
                      1981 SUPPLEMENTAL STOCK OPTION PLAN

                           Adopted December 17, 1981
                 Approved by the Shareholders February 24, 1982
                             Amended June 25, 1985
                            Amended October 21, 1986
            Amendment Approved by the Shareholders October 20, 1987
                             Amended April 19, 1989
           Amendment Approved by the Stockholders September 26, 1989
                           Amended February 15, 1990
               Amendment Approved by the Stockholders May 3, 1990
                           Amended February 27, 1992
               Amendment Approved by the Stockholders May 5, 1992
                           Amended February 18, 1993
               Amendment Approved by the Stockholders May 4, 1993
                           Amended February 10, 1994
              Amendment Approved by the Stockholders May 25, 1994
                            Amended October 14, 1994
            Amendment Approved by the Stockholders December 20, 1994
                           Amended February 21, 1996
              Amendment Approved by the Stockholders May 14, 1996
                            Amended August 19, 1996



1.               PURPOSE.

         (a)     The purpose of the Plan is to provide a means by which
selected key employees and directors of and consultants to Caere Corporation, a
California corporation (the "Company"), and its affiliates, as defined in
subparagraph 1(b), may be given an opportunity to purchase stock of the
Company.

         (b)     The word "affiliate" as used in the Plan means any parent
corporation or subsidiary corporation of the Company as those terms are defined
in Sections 424(e) and (f), respectively, of the Internal Revenue Code of 1986,
as amended from time to time (the "Code").

         (c)     The Company, by means of the Plan, seeks to retain the
services of persons now holding key positions, to secure and retain the
services of persons capable of filling such



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positions, and to provide incentives for such persons to exert maximum efforts
for the success of the Company.

         (d)     The Company intends that the options issued under the Plan not
be incentive stock options as that term is used in Section 422 of the Code.

2.       ADMINISTRATION.

         (a)     The Plan shall be administered by the Board of Directors (the
"Board") of the Company unless and until the Board delegates administration to
a committee, as provided in subparagraph 2(c).  Whether or not the Board has
delegated administration, the Board shall have the final power to determine all
questions of policy and expediency that may arise in the administration of the
Plan.

         (b)     The Board shall have the power, subject to, and within the
limitations of, the express provisions of the Plan:

                 (1)      To determine from time to time which of the persons
eligible under the Plan shall be granted options; when and how the option shall
be granted; the provisions of each option granted (which need not be
identical), including the time or times during the term of each option within
which all or portions of such option may be exercised; and the number of shares
for which an option shall be granted to each such person.

                 (2)      To construe and interpret the Plan and options
granted under it, and to establish, amend and revoke rules and regulations for
its administration.  The Board, in the exercise of this power, may correct any
defect, omission or inconsistency in the Plan or in any option agreement, in a
manner and to the extent it shall deem necessary or expedient to make the Plan
fully effective.

                 (3)      To amend the Plan as provided in paragraph 10.





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                 (4)      Generally, to exercise such powers and to perform
such acts as the Board deems necessary or expedient to promote the best
interests of the Company.

         (c)     The Board may delegate administration of the Plan to a
committee composed of one (1) or more members of the Board, all of the members
of which committee may (but need not) be, in the discretion of the Board,
non-employee directors and/or outside directors, as defined by the provisions
of subparagraphs 2(d) and 2(e), respectively.  If administration is delegated
to a committee, the committee shall have, in connection with the administration
of the Plan, the powers theretofore possessed by the Board, including the power
to delegate to a subcommittee of two or more outside directors any of the
administrative powers the committee is authorized to exercise, subject,
however, to such resolutions, not inconsistent with the provisions of the Plan,
as may be adopted from time to time by the Board.  The Board may abolish the
committee at any time and revest in the Board the administration of the Plan.

         (d)     The term "non-employee director," as used in this Plan, shall
mean a director who either (i) is not a current employee or officer of the
Company or its parent or subsidiary, does not receive compensation (directly or
indirectly) from the Company or its parent or subsidiary for services rendered
as a consultant or in any capacity other than as a director (except for an
amount as to which disclosure would not be required under Item 404(a) of
Regulation S-K ("Regulation S-K") promulgated pursuant to the Securities Act of
1933 (the "Securities Act"), does not possess an interest in any other
transaction as to which disclosure would be required under Item 404(a) of
Regulation S-K, and is not engaged in a business relationship as to which
disclosure would be required under Item 404(b) of Regulation S-K; or (ii) is
otherwise considered a "non-employee director" for purposes of Rule 16b-3
promulgated under the Securities Exchange Act of 1934, as amended (the
"Exchange Act").





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         (e)     The term "outside director," as used in this Plan, shall mean
a director who either (i) is not a current employee of the Company or an
"affiliated corporation" (within the meaning of Treasury regulations
promulgated under Section 162(m) of the Code), is not a former employee of the
Company or an "affiliated corporation" receiving compensation for prior
services (other than benefits under a tax qualified pension plan), was not an
officer of the Company or an "affiliated corporation" at any time, and is not
currently receiving direct or indirect remuneration from the Company or an
"affiliated corporation" for services in any capacity other than as a director,
or (ii) is otherwise considered an "outside director" for purposes of Section
162(m) of the Code.

3.       SHARES SUBJECT TO THE PLAN.

         (a)     Subject to the provisions of paragraph 9 relating to
adjustments upon changes in stock, the stock that may be sold pursuant to
options granted under the Plan shall not exceed in the aggregate three million
five hundred ninety-five thousand (3,595,000) shares of the Company's common
stock; provided, however, that such aggregate number of shares shall be reduced
to reflect the number of shares of the Company's common stock that have been
sold pursuant to, or may be sold pursuant to outstanding options granted under,
the Company's 1981 Incentive Stock Option Plan to the same extent as if such
sales had been made or options had been granted pursuant to this Plan.  If any
option granted under the Plan shall for any reason expire or otherwise
terminate without having been exercised in full, the stock not purchased under
such option shall again become available for the Plan.

         (b)     The stock subject to the Plan may be unissued shares or
reacquired shares, bought on the market or otherwise.





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         (c)     Subject to the provisions of paragraph 9 relating to
adjustments upon changes in stock, no person shall be eligible to be granted in
any calendar year options under this Plan covering more than an aggregate of
three hundred thousand (300,000) shares of the Company's common stock, when
combined with options granted in the same calendar year under the Company's
1981 Incentive Stock Option Plan.  Shares subject to an option that is canceled
shall continue to be counted against the maximum number of shares that may be
covered by options granted to a person pursuant to this subparagraph 3(c).  If
an option is amended, exchanged or otherwise altered in a manner that results
in a reduction of the exercise price, such transaction shall be deemed to be a
cancellation of the original option and the grant of a new option for purposes
of this subparagraph.  In such event, both the original option and the new
option shall be counted in the applicable year against the maximum limitation
specified by this subparagraph in accordance with regulations promulgated under
Section 162(m) of the Code.

4.       ELIGIBILITY.

         Options may be granted only to key employees (including officers),
directors of or consultants to the Company or its affiliates.

5.       OPTION PROVISIONS.

         Each option shall be in such form and shall contain such terms and
conditions as the Board or the committee shall deem appropriate.  The
provisions of separate options need not be identical, but each option shall
include (through incorporation of provisions hereof by reference in the option
or otherwise) the substance of each of the following provisions:

         (a)     The term of any option shall not be greater than ten (10)
years from the date it was granted.





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         (b)     The exercise price of each option shall be not less than
eighty-five percent (85%) of the fair market value of the stock subject to the
option on the date the option is granted.

         (c)     The purchase price of stock acquired pursuant to an option
shall be paid, as specified in the option, either (i) in cash at the time the
option is exercised, or (ii) at the discretion of the Board or the committee,
(A) by delivery to the Company of other common stock of the Company, (B)
according to a deferred payment or other arrangement (which may include,
without limiting the generality of the foregoing, the use of other common stock
of the Company) with the person to whom the option is granted or to whom the
option is transferred pursuant to subparagraph 5(d), or (C) in any other form
of legal consideration that may be acceptable to the Board or the committee in
their discretion, either at the time of grant or exercise of the option.

         In the case of any deferred payment arrangement, interest shall be
payable at least annually and shall be charged at the minimum rate of interest
necessary to avoid the treatment as interest, under any applicable provisions
of the Code, of any amounts other than amounts stated to be interest under the
deferred payment arrangement.

         (d)     An option shall not be transferable except by will or by the
laws of descent and distribution, and shall be exercisable during the lifetime
of the person to whom the option is granted only by such person, unless
otherwise specified in the option, in which case the option may be transferred
upon such terms and conditions as are set forth in the option, as the Board or
the committee shall determine in its discretion, including (without limitation)
pursuant to a "domestic relations order" within the meaning of such rules,
regulations or interpretations of the Securities and Exchange Commission as are
applicable for purposes of Section 16 of the Exchange Act.  Notwithstanding the
foregoing, the person to whom an option is granted may,





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by delivering written notice to the Company, in a form satisfactory to the
Company, designate a third party who, in the event of the death of the
optionee, shall thereafter be entitled to exercise the option.

         (e)     The total number of shares of stock subject to an option may,
but need not, be allotted in periodic installments (which may, but need not, be
equal).  From time to time during each of such installment periods, the option
may be exercised with respect to some or all of the shares allotted to that
period, and/or with respect to some or all of the shares allotted to any prior
period as to which the option was not fully exercised.  During the remainder of
the term of the option (if its term extends beyond the end of the installment
periods), the option may be exercised from time to time with respect to any
shares then remaining subject to the option.  The provisions of this
subparagraph 5(e) are subject to any option provisions governing the minimum
number of shares as to which an option may be exercised.

         (f)     The Company may require any optionee, or any person to whom an
option is transferred under subparagraph 5(d), as a condition of exercising any
such option to give written assurances satisfactory to the Company stating that
such person is acquiring the stock subject to the option for such person's own
account not with any present intention of selling or otherwise distributing the
stock.  The requirement of providing written assurances and any assurances
given pursuant to the requirement, shall be inoperative if (i) the issuance of
the shares upon the exercise of the option has been registered under a then
currently effective registration statement under the Securities Act, or (ii) a
determination is made by counsel for the Company that such written assurances
are not required in the circumstances under the then applicable federal
securities laws.





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         (g)     An option shall terminate three (3) months after termination
of the optionee's employment with the Company or an affiliate, unless (i) the
termination of employment of the optionee is due to such person's permanent and
total disability, within the meaning of Section 422(c)(6) of the Code, in which
case the option may, but need not, provide that it may be exercised at any time
within one (l) year following such termination of employment; or (ii) the
optionee dies while in the employ of the Company or an affiliate, or within not
more than three (3) months after termination of such employment, in which case
the option may, but need not, provide that it may be exercised at any time
within eighteen (18) months following the death of the optionee by the person
or persons to whom the optionee's rights under such option pass by will or by
the laws of descent and distribution; or (iii) the option by its terms
specifies either (a) that it shall terminate sooner than three (3) months after
termination of the optionee's employment, or (b) that it may be exercised more
than three (3) months after termination of the optionee's employment with the
Company or an affiliate.  This subparagraph 5(g) shall not be construed to
extend the term of any option or to permit anyone to exercise the option after
expiration of its term, nor shall it be construed to increase the number of
shares as to which any option is exercisable from the amount exercisable on the
date of termination of the optionee's employment.

         (h)     The option may, but need not, include a provision whereby the
optionee may elect at any time during the term of his or her employment with
the Company or any affiliate to exercise the option as to any part or all of
the shares subject to the option prior to the stated vesting date of the option
or of any installment or installments specified in the option.  Any shares so
purchased from any unvested installment or option may be subject to a
repurchase right





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in favor of the Company or to any other restriction the Board or the committee
determines to be appropriate.

         (i)     To the extent provided by the terms of an option, the optionee
may satisfy any federal, state or local tax withholding obligation relating to
the exercise of such option by any of the following means or by a combination
of such means:  (1) tendering a cash payment; (2) authorizing the Company to
withhold from the shares of the common stock otherwise issuable to the
participant as a result of the exercise of the stock option a number of shares
having a fair market value less than or equal to the amount of the withholding
tax obligation; or (3) delivering to the Company owned and unencumbered shares
of the common stock having a fair market value less than or equal to the amount
of the withholding tax obligation.

6.       COVENANTS OF THE COMPANY.

         (a)     During the terms of the options granted under the Plan, the
Company shall keep available at all times the number of shares of stock
required to satisfy such options.

         (b)     The Company shall seek to obtain from each regulatory
commission or agency having jurisdiction over the Plan such authority as may be
required to issue and sell shares of stock upon exercise of the options granted
under the Plan; provided, however, that this undertaking shall not require the
Company to register under the Securities Act either the Plan, any option
granted under the Plan or any stock issued or issuable pursuant to any such
option.  If the Company is unable to obtain from any such regulatory commission
or agency the authority which counsel for the Company deems necessary for the
lawful issuance and sale of stock under the Plan, the Company shall be relieved
from any liability for failure to issue and sell stock upon exercise of such
options unless and until such authority is obtained.





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7.       USE OF PROCEEDS FROM STOCK.

         Proceeds from the sale of stock pursuant to options granted under the
Plan shall constitute general funds of the Company.

8.       MISCELLANEOUS.

         (a)     The Board or the committee shall have the power to accelerate
the time during which an option may be exercised, or the time during which an
option or any portion thereof will vest pursuant to subparagraph 5(e),
notwithstanding the provisions in the option stating the time during which it
may be exercised.

         (b)     Neither an optionee nor any person to whom an option is
transferred under subparagraph 5(d) shall be deemed to be the holder of, or to
have any of the rights of a holder with respect to, any shares subject to such
option unless and until such person has satisfied all requirements for exercise
of the option pursuant to its terms.

9.       ADJUSTMENTS UPON CHANGES IN STOCK.

         (a)     If any change is made in the stock subject to the Plan, or
subject to any option granted under the Plan (through merger, consolidation,
reorganization, recapitalization, stock dividend, dividend in property other
than cash, stock split, liquidating dividend, combination of shares, exchange
of shares, change in corporate structure or otherwise), appropriate adjustments
will be made in the class(es) and maximum number of shares subject to the Plan
pursuant to subparagraph 3(a), the class(es) and maximum number of shares that
may be subject to options pursuant to subparagraph 3(c) and the class(es) and
number of shares and price per share of stock subject to outstanding options.

         (b)     In the event of: (l) a dissolution or liquidation of the
Company; (2) a merger or consolidation in which the Company is not the
surviving corporation; (3) a reverse merger in





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which the Company is the surviving corporation but the shares of the Company's
common stock outstanding immediately preceding the merger are converted by
virtue of the merger into other property, whether in the form of securities,
cash or otherwise; or (4) any other capital reorganization in which more than
fifty percent (50%) of the shares of the Company entitled to vote are exchanged
then, at the sole discretion of the Board to the extent permitted by law, (i)
any surviving corporation shall either assume options outstanding under the
Plan or substitute similar options for those outstanding under the Plan, (ii)
the time during which options outstanding under the Plan may be exercised shall
be accelerated and the options terminated if not exercised prior to such event,
or (iii) options outstanding under the Plan shall continue in full force and
effect.

10.      AMENDMENT OF THE PLAN.

         (a)     The Board at any time, and from time to time, may amend the
Plan.  However, except as provided in paragraph 9 relating to adjustments upon
changes in stock, no amendment shall be effective unless approved by the
stockholders within twelve (12) months before or after the adoption of the
amendment, where the amendment will:

                 (i)      Increase the number of shares reserved for options
under the Plan; or

                 (ii)     Modify the Plan in any other way if such modification
requires stockholder approval in order for the Plan to comply with the
requirements of Rule 16b-3 promulgated under the Exchange Act.

         (b)     Rights and obligations under any option granted before
amendment of the Plan shall not be altered or impaired by any amendment of the
Plan, except with the consent of the person to whom the option was granted.





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         (c)     The Board may in its sole discretion submit any other
amendment to the Plan for stockholder approval, including, but not limited to,
amendments to the Plan intended to satisfy the requirements of Section 162(m)
of the Code and the regulations promulgated thereunder regarding the exclusion
of performance-based compensation from the limit on corporate deductibility of
compensation paid to certain executive officers.

11.      TERMINATION OR SUSPENSION OF THE PLAN.

         (a)     The Board may suspend or terminate the Plan at any time.
Unless sooner terminated, the Plan shall terminate on January 31, 2000.  No
options may be granted under the Plan while the Plan is suspended or after it
is terminated.

         (b)     Rights and obligations under any option granted while the Plan
is in effect shall not be altered or impaired by suspension or termination of
the Plan, except with the consent of the person to whom the option was granted.

12.      EFFECTIVE DATE OF PLAN.

         The Plan shall become effective as determined by the Board, but no
options granted under the Plan shall be exercised unless and until the Plan has
been approved by the stockholders and, if required, an appropriate permit has
been issued by the Commissioner of Corporations of the State of California.





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